Computer systems are currently in wide use. Some computer systems provide on-line web services to a plurality of different users.
One example of such a computing system is an electronic mail system. Electronic mail (e-mail) systems often allow users to create electronic mail accounts by entering user-specific data, or other data, and to set various properties or functional characteristics of the account. By way of example, when a user sets up an e-mail account, the user may be provided with the ability to not only use the e-mail account for sending and receiving messages, but also to set various filtering and forwarding options. The filtering options may allow the user to set filter settings so that messages can be processed differently, depending on whether they meet filter criteria in the filter settings. For instance, the user may be able to set up an e-mail account and then set a forwarding option so that the newly-created e-mail account will forward all messages (or filtered messages, which are messages that pass any filter settings the user has set) to a second e-mail account.
There can be some incentives to use such a system maliciously. For instance, some networks (such as social networks) may require a user to have a unique e-mail account in order to set up a social network account. However, there may be incentives for a user to have multiple different social network accounts. Therefore, there may be an incentive for a single user to create multiple different e-mail accounts so the user can have multiple different social network accounts. If the number of multiple different e-mail accounts is a relatively large number of accounts, it can be difficult for the user to manage those accounts. Therefore, there may also be incentive for the user to forward all of those multiple e-mail accounts to a single e-mail account. The multiple accounts that are forwarded to the single account are referred to herein as collection accounts. The destination account that receives the forwarded messages from the collection accounts is referred to herein as a dropbox account.
Recently, spammers and abusers have created millions of malicious collection accounts and forwarded them to a relatively small number of dropbox accounts. The creation of these malicious collection accounts and dropbox accounts impacts the electronic mail services provided by service providers. Just setting up the accounts utilizes server system resources. Also, the forwarded messages from the collection accounts to the dropbox accounts can number many millions of e-mails messages. This increases the latency in an e-mail service offered by the service provider. This can cause delays in delivering e-mails for millions of legitimate users.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.